Panasonic CS-A7DKD Service Manual page 28

CS-A7DKD CU-A7DKD / CS-A9DKD CU-A9DKD / CS-A12DKD CU-A12DKD /
8.5.14. Deicing Control
Deice starts to prevent frosting at outdoor heat exchanger.
• Normal Deicing
Deice operations detection commences after 30 minutes of Heating operation starts or 60 minutes after previous deice
operation. If the TRS (Thermal Reed Switch) senses the outdoor piping temperature drops to -3°C (TRS CLOSE) or less for
50 sec. continuously during compressor is in operation, deice will start.
(There is no detection during Outdoor Fan stops.)
• Overload Deicing
During heating operation, if the outdoor Fan OFF duration (due to overload control) is accumulated up to 60 minutes and
after compressor starts for 1 minutes, deicing starts.
• Deicing ends when
1. 12 minutes after deicing operation starts;
2. TRS senses the outdoor piping temperature rises to 4°C (TRS OPEN).
Deicing will not end immediately as time delay (Td) is valid as shown below.
• Once deicing operation starts, it will not end for 60 seconds.
• After deicing operation, compressor stops for 30 seconds and 4-way valve stays at cooling position for 10 seconds.
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